The present invention is directed to a stabilization system for the printing of signatures to prevent shock and vibrations generated from the conveyance of the signatures from adversely affecting the quality of the printing on the signatures.
Signatures of which books or magazines are composed may be conveyed by a conveyance system in order to accomplish a variety of functions, one of which includes the application of printing to the signatures. One problem with such a system is that vibrations generated by the conveyance system may cause the printing to be blurred or otherwise adversely affected. In some relatively forgiving applications, such as the printing of a name and address within a white box on a magazine cover, slight blurring of the printing may be acceptable as long as the printing is legible. However, in applications with more stringent printing requirements, such as the printing of the interior pages of a book or magazine, such blurring is unacceptable.
U.S. Pat. No. 4,121,818 to Riley, et al. discloses a signature collating and binding system in which various printing operations are performed on signatures which are conveyed by a chain conveyor. As shown in FIGS. 4A and 4B, a number of signatures 34 are conveyed by a pair of spaced chains 90 past a label printer 94 composed of a number of individual print heads 56. In FIG. 3, a number of signatures 34 are conveyed by a collating chain 44 past a signature printer 54 composed of five printheads 56 so that five lines of printing may be printed within a one-inch width. There is no disclosure in the Riley, et al. patent that the printing operations are completely shielded from vibrations generated by the signature conveyors.